Carpet wear testing is a particularly important facet of the carpet industry. Carpets are normally expected to last 20 or more years and are often sold with warranty periods of five or ten years. Thus, it is readily apparent that the industry can ill-afford to wait five, ten or even twenty years before determining the wear and durability capabilities of a particular carpet. Carpet wear testers have been developed which utilize a pneumatic impactor to repetitively impinge upon a carpet sample. The carpet sample is normally clamped to a test table and moved relative to the pneumatic impactor, thus causing the location of the impacts on the carpet to traverse the carpet sample in a repeated pattern. The clamps in known carpet testers have employed springs for keeping the carpet sample under constant or nearly constant tension while it is impacted by a simulated shoe or other wear producing device. Known carpet wear testers have employed cams and mechanical linkages to produce repeated traverse patterns over the carpet test samples but have in general been limited to one or few test patterns.
Human foot traffic, however, is extremely varied and multidirectional. A foot step involves not only the forces of a downwardly directed impact but shear on the floor covering as the foot moves forward while impacting and lifting from the surface. Prior art testing equipment has failed to properly simulate these forces or has utilized a unidirectional shear simulation.
Conventional industry tests work carpet samples as isolated units, for example by lining a rotating drum with the sample and oscillating an independent ball or weight for repeated random impacts. Such a test produces a carpet which is fully worked over its entire surface. It does not provide any range of data. Furthermore, this type of test does not take into account the support or lack thereof provided by the cushion or backing material.
While known carpet testers are effective for producing wear in carpets, they lack the flexibility to address current issues in carpet wear. Conventional carpet testers produce worn samples of carpet which may be evaluated but do not produce real time feedback of the material properties of the carpet sample being tested which may be used in real time to modify the actions of the carpet tester. Furthermore, known carpet testers do not allow computer control of the wear impactor's traversing course nor the use of an actual database of the dynamics of a person traversing a carpet to control a carpet tester.
What is needed is a floor covering testing apparatus which mimics the actual intensity and direction of forces applied under actual environmental conditions which permits analysis of the changing attributes of a floor covering system over time and which generates a tested specimen which provides a wide range of testing data.